Email is one of the most prevalent forms of communication amongst individuals via the Internet. Traditionally, email messages are created by an originating user, and transmitted via the originating user's Internet-connected email server, to a receiving user's Internet-connected email server. In some circumstances, the recipient's email server may then, periodically, deliver copies of the message to an email client application, which may be operating on or via one or more of the recipient's personal electronic devices. The recipient can then use one or more electronic devices implementing email clients in order to view the received messages. In some circumstances, a web mail client associated with the recipient's email server may be accessible via the Internet to render email messages stored on the server.
With the proliferation of Internet-connected devices, email messages increasingly contain URLs referencing static content items accessible via the Internet. When an email client renders such a message, the content referenced by URLs may be automatically downloaded and displayed. Because URLs are nearly always much smaller in size than the resources they are referencing, incorporating URLs in this way facilitates broad dissemination of graphical content via email, while minimizing outgoing server bandwidth requirements and recipient email storage requirements.
In some cases, Internet-based services may use information about the recipient to customize the content or appearance of email messages. For example, a retailer sending an advertising email to a target customer list that includes individual names and email addresses, may incorporate each recipient's name into the subject line of each email in order to personalize the message and attract the recipient's attention. As another example, an apparel retailer having customer home address information conducting an advertising campaign in January may advertise snow gear to customers having a home address in Minnesota, while advertising light jackets to customers having a home address in Arizona.
However, the content of such personalized messages is typically fixed at or before the time the email message is transmitted by the originator. Therefore, if the Minnesota resident is spending the winter in Arizona, they will still view snow gear advertisements when opening the email message. Also, if there is a delay and the recipient opens the email message in March or April, they will still view snow gear advertisements, even though it may be no longer relevant to the recipient.